JSFiddle - React, Tailwind, and code Playground

HTML

<ul>
    <li>Um</li>
    <li>Dois</li>
    <li>Três</li>
</ul>

CSS

li {
    transition: border-bottom .2s linear;
    border-bottom: 0px solid red;
    padding: 10px;
    display: inline;
}

li:hover {
    border-bottom: 5px solid red;
}